Re: [IBIS-Users] How Ramp data is processed ?

Hello Bob

Thanks for your answer.

Is there any theoretical explanation why we can assume that W(t)pu =
1-W(t)pd ?
As for the second approach I didn't understood it. please apply more
details.

Thanks

Itzik

Bob Ross wrote:

> Hello Itzik:
>
> One approach is simply to assume a relationship such as
>
> W(t)pu = 1-W(t)pd
>
> Another approach is to the same R_load to the other rail
> and to assume an amplitude adjusted and time scaled V(t)
> for that rail.
>
> Both approaches are assumptions and may still not
> produce results that correlate with the source data.
>
> Bob
>
> Itzik Peleg wrote:
>
>> Hello IBIS Users
>>
>> When only ramp data exist in the model.
>> As far as I understand the ramp rate is used to calculate the two
>> weight functions (one of the pull down and one for the pull up) that
>> describe this transition (high to low or low to high).
>>
>>
>> >From Ramp we got the V(t) that describe the transition (linear curve).
>> The resistor load is also known R_load.
>> We also got the I(V) curves for pullup and pulldown (I will mark this
>> function as I(V)pu and I(V)pd).
>> I will mark the weight function as W(t)pu for pullup and W(t)pd.
>> Then we can write this equation for the transition:
>>
>> V(t) = R_load* (I(V)pu * W(t)pu - I(V)pd * W(t)pd)
>>
>> In order to get the W(t)pu and W(t)pd we need one more equation.
>> What I am missing here ?
>> Can anyone point me to a relevant paper on this subject ?
>>
>> --
>> Regards
>>
>> Itzik Peleg Board Technology Group
>>
>> Marvell Semiconductor Israel Ltd
>> 6 Ha'mada St. Industrial Area
>> P.O.Box 692 Yokneam 20692 ISRAEL
>> Email - itzik.peleg@il.marvell.com
>> Tel - +972 4 9091192 Cell - +972 54 4452482
>> Fax - +972 4 9091501
>> WWW Page: http://www.marvell.com
>> ========================================================================
>> This message may contain confidential, proprietary or legally privileged
>> information. The information is intended only for the use of the
>> individual or entity named above. If the reader of this message is
>> not the intended recipient, you are hereby notified that any
>> dissemination,
>> distribution or copying of this communication is strictly prohibited.
>> If you have received this communication in error, please notify us
>> immediately by telephone, or by e-mail and delete the message from
>> your computer.
>>
>> Thank you!
>> ========================================================================
>>
>

-- 
Regards
Itzik Peleg 
Board Technology Group
Marvell Semiconductor Israel Ltd
6 Ha'mada St. Industrial Area
P.O.Box 692 Yokneam  20692  ISRAEL
Email - itzik.peleg@il.marvell.com
Tel   - +972 4  9091192  
Cell  - +972 54 4452482
Fax   - +972 4  9091501
WWW Page: http://www.marvell.com
========================================================================
This message may contain confidential, proprietary or legally privileged
information. The information is intended only for the use of the
individual or entity named above. If the reader of this message is not 
the intended recipient, you are hereby notified that any dissemination,
distribution or copying of this communication is strictly prohibited. 
If you have received this communication in error, please notify us 
immediately by telephone, or by e-mail and delete the message from 
your computer.
Thank you!
========================================================================
|------------------------------------------------------------------
|For help or to subscribe/unsubscribe, email majordomo@eda.org
|with just the appropriate command message(s) in the body:
|
|  help
|  subscribe   ibis       <optional e-mail address, if different>
|  subscribe   ibis-users <optional e-mail address, if different>
|  unsubscribe ibis       <optional e-mail address, if different>
|  unsubscribe ibis-users <optional e-mail address, if different>
|
|or email a written request to ibis-request@eda.org.
|
|IBIS reflector archives exist under:
|
|  http://www.eda.org/pub/ibis/email_archive/  Recent
|  http://www.eda.org/pub/ibis/users_archive/  Recent
|  http://www.eda.org/pub/ibis/email/          E-mail since 1993